Is there a one week Pregnant ? Pregnancy weeks count from the first day of your last menstrual period. Pregnancy becomes four-week when the fetus places into womb. So, there is no actually pregnancy or the presence of a baby before four weeks.
Fertilization occurs when ovulation starts after 2 weeks from the last menstrual period. Therefore, on the days of your 1st or 2nd week of pregnancy, there is actually no pregnancy yet. At the 3rd week of fertilization zigot passes through the womb (uterus). At the 4th week the womb reaches pregnancy and settles here. Fetus occurs in ultrasonication between the 5th and 6th weeks of pregnancy.
For this reason, pregnancy counts from four-week but not from 1, 2 or 3 week pregnant .
For example, a woman who menstruates every month may suspect of pregnancy if her last menstruate is in 1 August and there is no menstruation till 1 September. If she learns she is pregnant after an examination or pregnancy test, we can say she is four-week pregnant (not 1 week) because pregnancy is counted up from the first day of the last menstrual week.